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#include <algorithm>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <vector>
#include <random>
#include <numeric>

using namespace std;

#define PB push_back
#define MP make_pair
#define F first
#define S second
#define ALL(x) (x).begin(),(x).end()
#define SIZE(x) (int)(x).size()
#define CLEAR(tab) memset(tab, 0, sizeof(tab))
#define REP(x, n) for(int x = 0; x < (n); x++)
#define FOR(x, b, e) for(int x = (b); x <= (e); x++)
#define FORD(x, b, e) for(int x = (b); x >= (e); x--)
#define VAR(v, n) __typeof(n) v = (n)
#define FOREACH(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define DEBUG(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)

typedef long long int LL;
typedef pair<int,int> PII;
typedef vector<int> VI;

const int MXN = 1000000;
const int C = 262144;
const int INF = 1000000001;
const int MOD = 1000000007;

int n, k;

set<vector<int> > S;

int fast_pow(int x, int k) {
	int res = 1;
	int a = x;
	while(k) {
		if(k % 2) {
			res = ((LL)res * a) % MOD;
		}
		a = ((LL)a * a) % MOD;
		k /= 2;
	}
	return res % MOD;
}

int calc_inv(vector<int> &vec) {
	int res = 0;
	FOR(i, 1, n - 1)
		FOR(j, 0, i - 1)
			if(vec[i] < vec[j])
				res++;
	return res;
}

vector<int> compose(vector<int> &a, vector<int> &b) {
	vector<int> res;
	res.resize(SIZE(a));
	FOR(i, 0, n - 1)
		res[i] = b[a[i]];
	return res;
}

int total_inv = 0;

void add(vector<vector<int> > &perms) {
	bool dec = 1;
	vector<int> id;
	FOR(i, 0, n - 1)
		id.PB(i);
	S.insert(id);

	while(dec) {
		dec = 0;
		FOREACH(perm, perms)
			FOREACH(it, S) {
				auto vec = *it;
				vector<int> new_vec = compose(vec, *perm);
				if(S.find(new_vec) == S.end() ) {
					dec = 1;
					S.insert(new_vec);
					break;
				}
			}
	}
}

int gcd(int a , int b) {
	if(b == 0)
		return a;
	a %= b;
	return gcd(b, a);
}

int calc_res(int p, int q) {
	int d = gcd(p, q);
	p /= d;
	q /= d;

	return ((LL)p * fast_pow(q, MOD - 2)) % MOD;
}

void test() {
    scanf("%d %d", &n, &k);
	vector<vector<int> > perms;
	FOR(i, 1, k) {
		vector<int> perm;
		FOR(j, 1, n) {
			int x;
			scanf("%d", &x);
			x--;
			perm.PB(x);
		}
		perms.PB(perm);
	}
	add(perms);
	int total_inv = 0;
	FOREACH(it, S) {
		vector<int> vec = *it;
		total_inv = (total_inv + calc_inv(vec)) % MOD;
	}
	printf("%lld\n", calc_res(total_inv, SIZE(S)));
}

int main() {
	int te = 1;
//	scanf("%d", &te);
	while(te--)
		test();
	return 0;
}